It has been known in the past to utilize solar energy in the treatment of water and waste material and particularly a sludge resulting therefrom. For example, one is referred to the earlier work of Dr. B. K. Huang et al. In U.S. Pat. No. 4,240,210, Dr. Huang et al discloses a method and apparatus for utilizing solar energy in a water and waste management system. In the Huang et al system, it is provided at least one rotary chamber disposed within a drying structure having a transparent outer wall of substantial area. Water and/or waste material is directed into the rotary chamber and free water contained within the sludge material received within the chamber is drained therefrom. Solar radiation passes through the transparent outer wall of the drying structure and is collected about the wall structure of the rotary chamber. Solar energy in the form of heat is utilized to dry the sludge contained within the rotary drying chamber by directing air about and through the same. After the sludge is dried a predetermined or selected moisture content, the dried sludge is conveyed to an end portion of the rotary chamber where the sludge is deposited or collected. In the Huang et al disclosure, there is suggested an auger-type conveyor that is disposed within the rotary drying chamber itself and this auger-type conveyor is actually used to convey the dried sludge from the rotary drying chamber.